Flat bricks

Flat bricks are modern masonry bricks that are sanded so that they can be moved in a 1 - 3 mm thick layer of mortar. In contrast, conventional masonry blocks (block bricks) are moved in a mortar bed about 10 mm thick. Advantages of flat bricks in thin-bed mortar are:

• less mortar application required
• lower thermal conductivity, better thermal insulation values
• less moisture in the masonry time
• savings in masonry
• increased masonry compressive stress

Source: bauwion